The Democratic Unionist party is going on a "pub crawl of preconditions and the [British and Irish] governments need to call time on it", Mark Durkan, the leader of the nationalist Social Democratic and Labour party, has warned.

Three weeks out from the next set of intensive talks designed to restore a power-sharing, devolved executive to Northern Ireland, the traditional barrage of bar room insults has begun. The premiers in London and Dublin have spent all summer warning the province's fractious politicians that they may be drinking in the last chance saloon.

But the imposition of the so-called 'final' deadline on negotiations of November 24 by Tony Blair and Bertie Ahern is provoking growing resentment among unionists who have yet to overcome their instinctive suspicions of Sinn Fein and the IRA.

Warnings that it could be 2009 before both governments are free to concentrate on the issue again have yet to dragoon reluctant party leaders into agreeing a deal. Between October 11 and 13 the main parties and the two prime ministers will be locked away in a hotel in Scotland in an attempt to broker a deal.

Last week, Ian Paisley, the leader of the DUP, emerged from discussions in Downing Street saying he did not believe a settlement was achievable within the governments' tight timetable.

The last power-sharing assembly collapsed in late 2002 following allegations that Sinn Fein was operating a spy ring within Stormont, the building where the assembly meets in east Belfast. Those charged were eventually freed without trial when it emerged that the main suspect, Denis Donaldson, had formerly worked for British intelligence.

In December 2004, the DUP and Sinn Fein, the largest unionist and nationalist parties, nearly managed to agree on a 'comprehensive' deal that would have resurrected power-sharing. It broke down over the question of photographing IRA decommissioning and any residual goodwill vanished shortly afterwards following revelations that the IRA had been involved in the £26 million Northern Bank robbery.

Since then the IRA has decommissioned its weapons. Speaking in New York on Wednesday, Mr Durkan accused the DUP leader of adding fresh preconditions before the latest round of negotiations, including that the IRA now disband and that the republican movement hand over all the funds it had obtained through illegal racketeering operations during the Troubles.

"The key issue," the SDLP leader said, "is not disbandment. It is that all paramilitary groups cease to act as armies or militias, as police forces, political intelligence services or as crime gangs. That is what really matters.

"As for criminal assets, it is for the governments north and south to make clear that there will be no let up in recovering the proceeds of crime from any paramilitary group."

Optimists suggest that if a deal is to be done, it will only be secured in the final days before the November 24 deadline. The new demands, they say, are evidence that hard bargaining is under way.

On the republican side the main issue is when Sinn Fein will sign up to the province's policing board and officially support the police service of Northern Ireland.

Gerry Kelly, the party's policing and justice spokesman, yesterday signalled that the republican movement was moving towards making that commitment. He told the Belfast Telegraph that a historic decision to back the police could be "weeks rather than months" away once the executive was restored.

For Tony Blair, the stakes are also high this time around. Close to the end off his premiership, delivering a stable peace to Northern Ireland would be the icing on his political legacy.

In an effort to persuade unionists to engage, the Northern Ireland secretary, Peter Hain, has offered a number of inducements. He has suggested that grammar schools, popular in the unionist community but due to be abolished soon, could be saved by a reconstituted executive. Likewise a new set of higher rates, based on the capital value of homes but without any upper cap on liabilities, could be reformed if the assembly was reformed.

Much depends on the next report of the Independent Monitoring Commission (IMC), due out on October 4, which is expected to confirm that the IRA is continuing to move away from crime and paramilitary violence.

Ian Paisley has yet to be convinced. "If, as the IMC has said, that IRA discipline is needed to maintain 'the organisation on its chosen path', then it is obvious for all to see that the republican movement has some considerable distance still to travel on the path to real democracy," he said this week.

"Several incidents in recent weeks and days have [also] raised serious questions about Sinn Fein/IRA's commitment to exclusively peaceful and democratic means."